Table Of ContentZOOTAXA
991
Alterosa, a new caddisfly genus from Brazil
(Trichoptera: Philopotamidae)
ROGER J. BLAHNIK
Magnolia Press
Auckland, New Zealand
ROGER J. BLAHNIK
Alterosa, a new caddisfly genus from Brazil (Trichoptera: Philopotamidae)
(Zootaxa 991)
60 pp.; 30 cm.
23 May 2005
ISBN 1-877407-02-X (paperback)
ISBN 1-877407-03-8 (Online edition)
FIRST PUBLISHED IN 2005 BY
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ISSN 1175-5326 (Print edition)
ISSN 1175-5334 (Online edition)
Zootaxa 991: 1–60 (2005) ISSN 1175-5326 (print edition)
www.mapress.com/zootaxa/ ZOOTAXA 991
Copyright © 2005 Magnolia Press
ISSN1175-5334(online edition)
Alterosa, a new caddisfly genus from Brazil
(Trichoptera: Philopotamidae)
ROGER J. BLAHNIK
Department of Entomology, University of Minnesota, 1980 Folwell Ave., Room 219, St. Paul, Minnesota,
55108, U.S.A. ([email protected])
TABLE OF CONTENTS
ABSTRACT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Taxonomic History of Philopotaminae . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
MATERIALS AND METHODS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
GENERIC DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Alterosa, new genus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
SPECIES DESCRIPTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Alterosa beckeri, new species . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Alterosa bocainae, new species . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Alterosa boraceiae, new species . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Alterosa caparaonensis, new species . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Alterosa escova, new species . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Alterosa falcata, new species . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Alterosa fimbriata, new species . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Alterosa flinti, new species . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Alterosa fluminensis, new species . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Alterosa guapimirim, new species . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Alterosa holzenthali, new species . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Alterosa intervales, new species . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Alterosa itatiaiae, new species . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Alterosa jordaensis, new species . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Alterosa marinonii (Almeida & Duarte), new combination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Alterosa orgaosensis, new species . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Alterosa paprockii, new species . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Alterosa sanctaeteresae, new species . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Alterosa sanctipauli (Flint), new combination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Alterosa schadrackorum, new species . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Alterosa tripuiensis, new species . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
Alterosa truncata, new species . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
PHYLOGENETIC CONSIDERATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
Relationships within Alterosa . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
CONCLUDING COMMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
ACKNOWLEDGMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
LITERATURE CITED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
Accepted by R. Holzenthal: 29 Apr. 2005; published: 23 May 2005 3
ZOOTAXA ABSTRACT
991
The subgenera of Dolophilodes (Trichoptera: Philopotamidae), as recognized by Ross (1956), are
reconsidered. Sortosa Navás 1918, Thylakion Barnard 1934, Fumonta Ross 1956, and Sisko Ross
1956 are elevated to generic status, and an additional genus, Alterosa, is established to include 2
described species, Dolophilodes (Sortosa) sanctipauli Flint 1971 and Dolophilodes (Sortosa)
marinonii Almeida & Duarte 2003, and 20 new species, all from southern or southeastern Brazil.
New species described in Alterosa include: Alterosa beckeri,A. bocainae,A. boraceiae,A. capara-
onensis,A.escova,A. falcata,A. fimbriata,A. fluminensis,A. flinti,A. guapimirim,A. holzenthali,
A. intervales, A. itatiaiae, A. jordaensis, A. orgaosensis, A. paprockii, A. sanctaeteresae, A.
schadrackorum, A. tripuiensis, and A. truncata. Alterosa bocainae is designated the type species
for the genus. Species recognized as belonging to Sortosa include, in their original combinations:
Dolophilodesangulatus Schmid 1964, D.appendiculatus Flint 1967, D.bifidus Flint 1970, D.bis-
pinosus Flint 1967, Sortosachilensis Navás 1918, D.duplex Schmid 1964, D.dupliplex Flint 1983,
S. edwardi Ross 1956, D. elongatus Schmid 1964, D. elongatoides Flint 1967, S. flavipunctatus
Schmid 1955, S. michelbacheri Ross 1956, D paxilliferus Flint 1970, S. pectinifera Schmid 1958,
D.prolixus Flint 1983, D.scopulus Flint 1983, D.spectabilis Flint 1983, S.spinifera Schmid 1958,
D.spinosellus Flint 1970, and D.ventricostus Flint 1983. Species recognized as belonging to Thy-
lakion include, in their original combinations: Dolophilodes crenophilus Jacquemart and Statzner
1981, Thylakionforcipatus Barnard 1934, D.natalensis Morse 1974, and T.urceolus Barnard 1934.
Species recognized as belonging to Sisko include, in their original combinations: Sortosa oregona
Denning 1966 and Wormaldia sisko Ross 1949. The genus Fumonta is monotypic and includes, in
its original combination, Dolophilusmajor Banks 1914.
Key words: Trichoptera, Philopotamidae, Philopotaminae, Dolophilodes, Sortosa, Thylakion,
Sisko,Fumonta,Alterosa, new genus, new species, new status, new combination, caddisfly, Neotro-
pics, Brazil
INTRODUCTION
Until recently, only a single species in the subfamily Philopotaminae was known from
Brazil, Dolophilodes (Sortosa) sanctipauli Flint 1971. In 2003, a second species, Dolo-
philodes (Sortosa) marinonii, was described from Brazil by Almeida & Duarte. Flint
acknowledged at the time of its description that D. sanctipauli was distinctly different
from other species in the subgenus Sortosa, which has a substantial radiation of 20 species
in Chile. The 20 new species from Brazil described in this paper suggest that the philopot-
amine fauna of Brazil is as diverse as that of Chile. Most of these species have been col-
lected in relatively pristine headwater springs, streams or small rivers, and it is likely that
additional species remain to be collected in similar habitats, perhaps many more species.
All of the new species from Brazil share similarities to the two described species from the
region. The distinctiveness of these species has opened the question of their proper
generic placement.
4 © 2005 Magnolia Press BLAHNIK
Taxonomic History of Philopotaminae ZOOTAXA
991
The treatment of taxa in the current paper provided the opportunity to reassess Ross’s
(1956) classification of Philopotaminae. Although Ross can be considered a pioneer in
recognizing the difference and relative importance of primitive (plesiomorphic) versus
derived (apomorphic) characters for inferring relationships, he did not always reflect this
in the taxonomy he established. Some of the taxa he recognized were paraphyletic, based
on his own assessment of relationships. Ross's (1956) treatment of Philopotamidae is a
particularly cogent example of his recognition of genera that fail to conform to what are
now standard cladistic criteria, monophyly evidentially supported by synapomorphic char-
acters. Ross recognized one species within Philopotamidae, Paulianodes tsaratananae
Ross 1956, from Madagascar, as having retained primitive venational characters and justi-
fied the establishment of the subfamily Paulianodinae to accommodate it. The rationale
for this decision would be accepted under current cladistic methodology. Another clearly
derived lineage, including the genera Chimarra Stephens 1829 and Protarra Ross 1956
(now Chimarrhodella Lestage 1925), was left in the subfamily Chimarrinae. All of the
other genera of Philopotamidae were retained in the subfamily Philopotaminae, although
no synapomorphic characters were proposed to suggest monophyly of the taxon. He
placed the majority of the different genera that were then recognized from various parts of
the world into a single genus, Sortosa Navás 1918, and also established and placed here
several additional subgenera, namely Kisaura, Fumonta, and Sisko (Ross 1956). Subse-
quent to Ross's work, Ulmer (1957) recognized that the genus name Dolophilodes Ulmer
1909 has priority over Sortosa. Subgenera of Dolophilodes recognized by Ross include
Dolophilodes (North America and eastern Asia), Kisaura (eastern Asia), Fumonta (E.
North America), Sisko (North America), Sortosa (Chilean subregion of South America),
Hydrobiosella Tillyard 1924 (Australia, New Zealand, and New Caledonia), and Thylak-
ion Barnard 1934 (South Africa, Zaire). An additional monobasic subgenus, Dolophilodes
(Hisaura), was subsequently recognized by Kobayashi (1980), but this subgenus was
recently made a synonym of subgenus Dolophilodes (Kuhara 2005).
Within Philopotaminae, Ross (1956) did retain generic names for several distinctly
apomophic lineages, including Philopotamus Stephens 1829 (Europe), Wormaldia
MacLachlan 1865(widespread in the Old and New Worlds), and Gunungiella Ulmer 1913
(India and SE Asia). Doloclanes Banks 1937 was made a subgenus of Wormaldia and
Cabreraia Enderlein 1929 was considered a probable synonym of Wormaldia, although
not officially synonymized. In the same work, Zelobiosella Mosely 1953 was synony-
mized under subgenus Hydrobiosella. This accounts for all of the taxa then known in
Philopotaminae. Ross based his evolutionary discussion of the genera and subgenera of
Philopotaminae on what he called the “Sortosa ancestor,” a species more generalized than
any known descendent lineage. Although Ross discussed the apomorphic differences
among the lineages descended from this ancestor, the recognition of the genus Dolophilo-
des itself was based on the retention of the same primitive morphological features that
ALTEROSA GEN. NOV. © 2005 Magnolia Press 5
ZOOTAXA characterized the ancestor, including primitive wing venational and male genitalic charac-
991 ters. Thus Dolophilodes, sensu Ross 1956, was recognized based on plesiomorphic char-
acters. No apomorphic characters were adduced by Ross to suggest that either the genus-
level taxa he transferred to Dolophilodes, or the new subgenera he created constituted a
collectively monophyletic taxon, nor have any been proposed since. Ross’s taxonomic
treatment of Philopotaminae is the system from which modern taxonomic usage has
evolved, and was recognized by Fischer (1971) in his supplement to the Trichoptorum
Catalogus. However, the previously established generic names Sortosa, Thylakion, Dolo-
philodes, and Hydrobiosella were already continued in that usage by Ulmer (1957), who
acknowledged that Ross treated these taxa as subgenera. Ulmer’s paper included no dis-
cussion of the taxonomic status of new subgenera established by Ross.
Since Ross's (1956) treatment of Philopotamidae, several taxa have been given differ-
ent taxonomic status and also several additional genera have been described. Neboiss
(1977) resurrected Hydrobiosella to generic status when describing a number of additional
species from Tasmania. Cowley (1976) was the only author to actually describe a species
of Hydrobiosella under the genus name Dolophilodes. Kisaura, originally established as a
subgenus of Dolophilodes by Ross (1956), was elevated to full generic status by Malicky
(1993a). For both Hydrobiosella and Kisaura, generic recognition was based on the dis-
tinctiveness of the included taxa, but without any assessment of the monophyly of the spe-
cies remaining in the genus Dolophilodes. Doloclanes, considered by Ross (1956) a
subgenus of Wormaldia, has also subsequently been recognized as a genus (Schmid 1991;
Malicky 1993a, 1993b, 1994, 1995; Malicky and Chantaramongkol 1993, 1996; Mey
1993, 1996; Neboiss 1999). Although Schmid was the first author after Ross to recognize
Doloclanes as a genus, he did so without mentioning that Ross had reduced it to subge-
neric status, or discussing his reasons for elevating it. Additional new genera recognized
in Philopotamidae include Neobiosella Wise 1958, Cryptobiosella Henderson 1983, and
Xenobiosella Henderson 1983, all from New Zealand, Dolomyia Schmid 1991 and Dolo-
psyche Schmid 1991 from India, and Edidiehlia Malicky 1993 from Sumatra.
Of the new genera from New Zealand, Neobiosella is monotypic and still only known
from the holotype female. Cryptobiosella and Xenobiosella were established based on
their apomorphic differences from other philopotamid genera and analyzed within a cla-
distic framework that included New Zealand taxa, including Hydrobiosella, but were not
placed within a broader phylogenetic framework (Henderson 1983). Dolomyia and Dol-
opsyche have the same primitive venational characters used by Ross to define Dolophilo-
des, but are not easily placed in any of the subgenera he established. They are also unusual
in both having a spur formula of 3:4:4 rather than 2:4:4, as is common among all other
genera of Philopotamidae (including Paulianodes), with the exception of the genus Chi-
marra, with a derived spur formula of 1:4:4. The single unusual species placed in Edidie-
hlia was considered by Malicky to be close to Chimarra, and hence a member of the
subfamily Chimarrinae.
6 © 2005 Magnolia Press BLAHNIK
For those concerned with issues of monophyly, the taxonomic system, as it currently ZOOTAXA
991
stands, is disturbing at best, since some taxa are based on plesiomorphic characters and
others, while being defined by apomorphic characters, are recognized without any assur-
ance that the sister taxon is not left paraphyletic by its recognition. As an example, within
the phylogeny proposed by Ross, Gunungiella fell within the genus Wormaldia, and Philo-
potamus was considered a possible sister taxon to subgenus Thylakion in the genus Dolo-
philodes. Ross’s placement of these taxa was admittedly speculative, but accepting his
assessment of relationships, Gunungiella would appropriately be a synonym of Wormal-
dia, and the subgenera of Dolophilodes recognized by Ross would either have to be trans-
ferred to Philopotamus (the oldest available genus name), or Thylakion would have to be
recognized as a separate genus. The latter would require many of the other subgenera of
Dolophilodes recognized by Ross to be elevated to genera to retain the principle of generic
monophyly within a cladistic classification. At present I am not much more certain than
was Ross how these different lineages are related. This is a question that will require a
complete reassessment of the world taxa. Work on this front has begun using molecular
characters (Kjer et al. 2002, and unpublished data) and there are some tentative results, but
a much more complete taxon sampling and additional sequence data are required before
definitive conclusions can be reached. However, even at this point it seems likely, for
instance, that the taxa currently recognized as Dolophilodes (Thylakion) and Dolophilodes
(Sortosa) are more closely related to Hydrobiosella than to Dolophilodes (Dolophilodes).
This might have been expected based on biogeography alone, given the numerous studies
demonstrating the close relationship of the Chilean and Australian faunas, following the
pioneering studies of Brundin (1966).
In my description of new species from Brazil, I have been reluctant to add to this taxo-
nomic confusion. One solution is to follow the path first begun by Ulmer (1957), who
continued to recognize some subgeneric names used by Ross as genera. This path was
also followed by Neboiss and Malicky when Hydrobiosella and Kisaura were elevated to
generic status. Fortunately, the principle of monophyly can be observed even when the
relative relationships among equivalently ranked taxa has not been determined, provided
that each of the taxa, independently, is defined by apomorphic characters. Since Ross pro-
posed characters suggesting monophyly of each of the subgenera of Dolophilodes, genera
based on these names would represent an improvement over the current situation. The
genus Dolophilodes, as currently recognized, almost certainly does not represent a mono-
phyletic group, especially when including the subgenera Sortosa and Thylakion. More-
over, since Dolophilodes, sensu Ross, was defined by plesiomorphic characters, it is not
possible to assess the relationship of taxa he included within the genus to genera he
excluded, nor to genera described subsequently. Consequently, I propose that Sortosa,
Thylakion, Sisko, and Fumonta be removed from Dolophilodes and elevated to generic sta-
tus, based primarily on the defining characters originally proposed for the taxa or those
suggested by Ross (1956). A synopsis of the generic system for Philopotamidae recog-
ALTEROSA GEN. NOV. © 2005 Magnolia Press 7
ZOOTAXA nized in this paper is found in Table 1. The taxa currently recognized as Dolophilodes
991 (Sortosa)sanctipauli,Dolophilodes (Sortosa)marinonii, and the new species described in
this paper, are very different in a number of respects from species of Sortosa, and also
from the other genera recognized here. This paper establishes a new genus, Alterosa, to
accommodate these species. They share several apomorphic characters that indicate their
monophyly, as discussed in the generic diagnosis.
TABLE 1. Philopotaminae genera.
Genus Number of Species Distribution
Philopotamus Stephens 1829 15 + 1 fossil Europe
Dolophilodes Ulmer 1909 48a N America & Asia
Sisko Ross 1956 2 N America
Fumonta Ross 1956 1 Eastern N America
Sortosa Navás 1918 20 Chile
Thylakion Barnard 1934 4 South Africa, Zaire
Kisaura Ross 1956 22 Eastern Asia
Hydrobiosella Tillyard 1924 19 Australia, New Zealand, New
Caledonia
Alterosa, new genus 22 S & SE Brazil
Cryptobiosella Henderson 1983 4 New Zealand
Xenobiosella Henderson 1983 1 New Zealand
Neobiosella Wise 1958 1 New Zealand
Dolomyia Schmid 1991 1 India
Dolopsyche Schmid 1991 1 India
Wormaldia MacLachlan 1865 91 + 8 fossil widespread in Old and New
Worlds
Doloclanes Banks 1937 39 mostly Asia (1 in N America)
Gunungiella Ulmer 1913 62 Asia
Cabreraia Enderlein 1929 1 Canary Islands
a Including 7 species unplaced in the previous subgeneric system of Ross.
MATERIALS AND METHODS
Methods used for preparation of specimens are similar to those discussed in papers by
Blahnik (1998) and Blahnik and Holzenthal (2004). Genitalia of specimens were cleared
in either 12.5% KOH at room temperature for 6 or more hours, or in a solution of 85% lac-
8 © 2005 Magnolia Press BLAHNIK
tic acid heated at 125° C for about 30 minutes, followed by a rinse in distilled water, trans- ZOOTAXA
991
ferred to a solution of 80–95% EtOH, and then to glycerin for viewing and drawing, and
finally stored in a micro vial of glycerin for permanent storage, for specimens on pins, or
transferred back to alcohol for specimens stored in alcohol. Pencil drawings of genitalic
structures were made by use of an optical grid and inked with a technical pen and the aid
of a light table. Drawings of the wings, head and thoracic structures were rendered in
Adobe Illustrator®. I used a convention of indicating structures of segment VIII of the
male genitalia with a dashed line so as not to obscure features of segment IX, and because
structures of segment VIII are generally less diagnostic. Measurements of wings were
made to the nearest 0.1 mm. Females were not illustrated, mostly because the differences
among them, for those available, were at most very minor and not convincingly diagnostic.
Terminology conforms to that used by Blahnik (1998) and in common use among
other workers on Trichoptera. The term “intermediate appendage,” as used here, refers to
structures of de novo appearance within Philopotaminae. There is no implication that the
structures are homologous to structures called intermediate appendages in other taxa, or
even to structures called intermediate appendages in other genera of Philopotaminae.
Differences between species are generally distinctive and it should be easy to identify
specimens by comparison to the illustrations provided and reference to the species diag-
noses. However, because limited material is currently available for most species, it is
impossible to predict how much variation may occur within a species. The reader is there-
fore left to his own judgment if a specimen at hand does not conform to the illustrations
provided. Some structures will be found to vary, and it is also possible that additional spe-
cies remain to be discovered.
Each pinned specimen, or lot of specimens in alcohol, examined during the study was
barcoded (4 mil polyester, 8 x 14 mm, code 49) with a unique alphanumeric sequence
beginning with the prefix UMSP. The prefix is not meant to imply ownership by the Uni-
versity of Minnesota Insect Collection, but only to indicate that the specimen was data-
based at that collection. Specimen taxonomic and collection data are stored in Biota® (v.
2.0, Sinauer Associates, Inc.) (Colwell 2003). Specimen barcode information is included
for holotypes in the list of material examined. A detailed list of all material examined,
including individual barcode numbers, is maintained at UMSP and can be downloaded
from http://www.entomology.umn.edu/museum/databases/BIOTAdatabase.html.
Holotypes were deposited in the Museu de Zoologia, Universidade de São Paulo, Bra-
zil (MZUSP), and paratypes in the same institution, as well as in the collections of the Uni-
versity of Minnesota, St. Paul (UMSP) and the National Museum of Natural History,
Smithsonian Institution, Washington, D.C. (NMNH), as designated in the species descrip-
tions.
ALTEROSA GEN. NOV. © 2005 Magnolia Press 9
ZOOTAXA GENERIC DESCRIPTION
991
Alterosa, new genus
Type species: Alterosa bocainae, new species.
The single character most useful for diagnosing Alterosa, and which may be uniquely apo-
morphic, is the structure of the phallobase of the male (Figs. 6D, 8D, 9D), which is tubular
basally and lacks the basodorsal expansion common in most philopotamids, including spe-
cies in the subfamily Chimarrinae. Other characters of the male genitalia useful, in combi-
nation, to diagnose the genus include: intermediate appendages positioned mesally to the
preanal appendages (Figs. 6A,B; 10A,B), absence of ventral processes on any of the termi-
nal segments of the male genitalia, and sternum IX with the posteroventral margin dis-
tinctly produced and widely truncate ventrally (Figs. 9A,B; 10A,B) and the posterodorsal
margin acutely articulating with the tergum (Figs. 6A, 9A). Preanal appendages arise from
the base of tergum X (Fig. 6A, 10A), rather than the dorsal margin of sternum IX (as is
typical in Sortosa, see Ross 1956, figs. 36A, 37A, 38A). In species in which the preanal
appendages are not secondarily modified (Fig. 9A), they are relatively simple in structure,
elongate and finger-like (Figs. 6A, 11A). Venation (Fig. 1) is primitive for Philopotamidae
and very similar to Sortosa and Hydrobiosella. Female genitalia (Fig. 4), like those of
most genera of Philopotaminae, excluding Dolophilodes,Fumonta, and Philopotamus, are
elongate and tapered, with very long, articulated apodemes from the anterior margin of
sternum VIII and tergum IX.
Adult. Color of pinned, dry specimens dark brown overall with contrasting small light
brown or yellowish spots on forewings, these sometimes arranged in irregularly linear
arrays near costal margins; legs, palps, and antennae usually paler in color. Three ocelli
present, prominent. Eyes with short projecting setae between the ommatidia. Maxillary
palps (Fig. 2) 5-segmented, relatively short: 1st segment very short, usually broadly
joined (often apparently fused) to 2nd segment, usually with a few setae on apicomesal
margin; 2nd segment short, globose, with numerous elongate setae on apicomesal surface;
3rd segment relatively short, about 3 or 4x length of segment 2; 4th segment very short,
about 2x as long as wide; 5th segment longer than segment 3, variable in length among
species. Setal warts of head (Fig. 3) well developed; posterolateral warts large, typical of
Philopotamidae; posterior setal warts rounded, separated mesally; anteromesal setal wart
large, subtriangular, notched mesally to accommodate anterior ocellus, laterally fused to
anterior setal warts; fused anterior and anteromesal warts roughly M-shaped. Prothorax
with rounded mesal setal warts, slightly separated mesally, laterally with indistinctly
defined setal areas. Wing venation (Fig. 1) primitive (forewing with forks 1–5 present,
hind wing with fork 4 missing, anal veins of hind wing reaching wing margin); fork 1 of
forewing branching just proximal to discal crossvein; s,r-m, and m crossveins of forewing
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